Israel's chief negotiator will go to Egypt for "decisive" talks on a cease-fire with Hamas, officials said Tuesday, as the sound of battles between Israeli troops and Palestinian militants rang out in the crowded streets of Gaza City.
With international outrage mounting over the toll on Gaza's civilians, Israel's decision to send Defense Ministry official Amos Gilad to Egypt on Thursday could be a signal of progress. Gilad had postponed the trip for days.
Diplomatic efforts to end 18 days of fighting have moved slowly, in part because of the wide gaps between Israel and Hamas, who do not negotiate directly.
Israel says it will push forward with the offensive until Hamas ends all rocket fire on southern Israel, and there are guarantees the Iranian-backed militant group will stop smuggling weapons into Gaza through the porous Egyptian border.
Hamas has said it will only observe a cease-fire if Israel withdraws from Gaza.
Also on Tuesday Israel's navy halted an Iranian ship carrying aid into the Gaza Strip, Reuters reported.
Iran does not recognize Israel and has been supporting Palestinians in Gaza during the conflict with Israel. Israel has accused Iran of supplying arms to Hamas militants, while Tehran says it gives the Islamists moral, financial and humanitarian support.
Iran claimed the ship was carrying 200 tons of food and medicine "for distribution among the blockaded people of Gaza," Reuters reported.
Much of the diplomacy focuses on an area of southern Gaza just across the Egyptian border that serves as a weapons smuggling route, making Egypt critical to both sides in any deal.
Israel wants smuggling tunnels along the border sealed and monitored as part of any deal, and has been bombing the tunnels throughout the campaign.
The push into the Tel Hawwa neighborhood was the farthest Israel has moved into Gaza City, and brought ground forces within a mile (1.5 kilometers) of the crowded city center. Palestinian hospital officials say more than 900 Palestinians, half of them civilians, have been killed over more than two weeks of fighting.
Palestinian rocket fire has been greatly reduced, but not halted altogether, since the offensive was launched. Some 15 rockets and mortar shells were fired toward Israel Tuesday, causing no injuries, the army said. A total of 13 Israelis have died since Dec. 27.
U.N. chief Ban Ki-moon was headed to the region Tuesday to press for a cease-fire, and a Hamas delegation resumed talks in Cairo with Egyptian intelligence officials.
Israeli military officials say that depending on what happens with what they described as "decisive" talks in Cairo, Israel will either move closer to a cease-fire or press on with an even tougher stage of its offensive. They spoke on condition of anonymity because they were discussing sensitive policy matters.
Prime Minister Ehud Olmert has vowed to press forward with an "iron fist," despite growing international calls for an end to the fighting.
Israel's army has largely avoided the difficult terrain of Gaza City's narrow alleyways and crowded neighborhoods.
Palestinian medical officials reported at least 21 people killed in fighting Tuesday throughout Gaza, though the Israeli army suggested the number could be higher.
One resident, Khader Mussa, said he fled his house while waving a white flag as the Israeli forces advanced. He spent the night huddling in the basement of a relative with 25 other people, including his pregnant wife and his parents.
"Thank God we survived this time and got out alive from here. But we don't know how long we'll be safe in my brother's home," Mussa, 35, told The Associated Press by telephone.
Several buildings were on fire, witnesses said, including a lumberyard. The sounds of battle could be heard clearly around the city of 400,000 as the Israeli forces, backed by artillery and attack helicopters, moved in. Israeli gunboats shelled the coast from the west.
The Israeli military said it carried out some 60 airstrikes overnight, hitting groups of Hamas militants holed up in a hotel, a house and a mosque. It said it also struck 15 squads of gunmen, rocket launching sites and 15 smuggling tunnels along the Egyptian border.
The army said it had killed or wounded about 30 militants, and that three soldiers were wounded in overnight fighting. Among them was an officer who was seriously wounded when a bomb exploded in a northern Gaza house that he was searching. Weapons, including a machine gun, were later found in the house, the military said.
Dr. Moaiya Hassanain, a Palestinian Health Ministry official, said dozens of calls for ambulances had been received, but they could not be dispatched because of the fighting.
The Gaza fighting has raised tensions around the region and galvanized anger toward Israel throughout the Arab world. On Tuesday, at least one gunman opened fire at an Israeli army patrol along the desert border between Israel and Jordan, the military said. There were no casualties, and Jordan said the claim was "baseless."
There was a similar shooting on the Israel-Syria border on Sunday, and last week militants in Lebanon fired rockets into an Israeli town in an apparent attempt to draw Israel into a second front.
The Israeli military has tightly controlled information from the battlefield, but indications have been that Hamas has not put up a serious fight.
Of the nine Israeli soldiers killed during the offensive, four were killed in "friendly fire incidents," a military inquiry concluded. Repeated Hamas claims of spectacular attacks on the Israelis have turned out to be false.
Speaking in parliament on Tuesday, Israel's military chief said his troops have achieved a lot but "still have work to do" in fighting Hamas in Gaza.
"The soldiers are doing exceptional work, with many achievements in inflicting damage on Hamas, its infrastructure, its government and military wing," he said.
But the fighting has raised concerns about a looming humanitarian disaster in Gaza, where hundreds of thousands of people are without power and running water.
The Israeli army said about 100 truckloads of humanitarian aid, including wheat, flour and medical supplies, were expected to be let into the territory on Tuesday. The aid was sent through during a daily three-hour lull that Israel has declared to allow humanitarian supplies to be delivered.
In Brussels, the European Union's aid chief said Tuesday that Israel has not respected international humanitarian aid during the war. EU Commissioner Louis Michel, speaking in a published interview, cited the high number of civilian casualties and difficulties of delivering aid to the needed.
In Oslo, Norway, meanwhile, the head of the U.N. agency for Palestinian refugees, Karen Abu Zayd, urged the Israeli army to do more to allow supplies into the besieged area.
"We are getting a lot of help from the Israeli Defense Forces on the one crossing that's open to get more and more trucks in, but it's just not enough," she said.
The Associated Press contributed to this report.